There's a few credit cards I hardly ever use so I don't even carry them with me. I decided today to redeem any points and close them...
I call the service center and they ask me for the account number. The conversation went something like this -
alex: I don't have it with me ...
rep: let's see I can pull it up with your social, can I get your social security number?
alex: yeah, it's ###-##-####
rep: ok, I'll be right back..
(20 seconds later)
rep: alright mr talarico - can I get the last four of your social to verify your account?
alex: uh... ####
rep: thanks, how can I help you today?
... so, as you can see they have great security measures in place at compass bank as well.